/*
 * Copyright (c) 1996-1999 by Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 */

/*!
 * \file
 */

/* This file is _WIN32 only */
#ifdef _WIN32

#include "inet_pton.h"

#if (NTDDI_VERSION < NTDDI_VISTA)

/*!
 * \brief format an IPv4 address
 *
 * \return `dst' (as a const)
 *
 * \note
 *	\li (1) uses no statics
 *	\li (2) takes a u_char* not an in_addr as input
 */
static const char *inet_ntop4(const u_char *src, char *dst, socklen_t size)
{
        char tmp[sizeof("255.255.255.255") + 1] = "\0";
        int octet;
        int i;

        i = 0;
        for (octet = 0; octet <= 3; octet++) {

                if (src[octet] > 255) {
                        //__set_errno (ENOSPC);
                        return (NULL);
                }
                tmp[i++] = '0' + src[octet] / 100;
                if (tmp[i - 1] == '0') {
                        tmp[i - 1] = '0' + (src[octet] / 10 % 10);
                        if (tmp[i - 1] == '0')
                                i--;
                } else {
                        tmp[i++] = '0' + (src[octet] / 10 % 10);
                }
                tmp[i++] = '0' + src[octet] % 10;
                tmp[i++] = '.';
        }
        tmp[i - 1] = '\0';

        if ((socklen_t)strlen(tmp) > size) {
                //__set_errno (ENOSPC);
                return (NULL);
        }

        return strcpy(dst, tmp);
}

#ifdef INET_IPV6
/*!
 * \brief convert IPv6 binary address into presentation (printable) format
 */
static const char *inet_ntop6(const u_char *src, char *dst, socklen_t size)
{
        /*
         * Note that int32_t and int16_t need only be "at least" large enough
         * to contain a value of the specified size.  On some systems, like
         * Crays, there is no such thing as an integer variable with 16 bits.
         * Keep this in mind if you think this function should have been coded
         * to use pointer overlays.  All the world's not a VAX.
         */
        char tmp[sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")], *tp;
        struct
        {
                int base, len;
        } best, cur;
        u_int words[8];
        int i;

        /*
         * Preprocess:
         *	Copy the input (bytewise) array into a wordwise array.
         *	Find the longest run of 0x00's in src[] for :: shorthanding.
         */
        memset(words, '\0', sizeof words);
        for (i = 0; i < 16; i += 2)
                words[i / 2] = (src[i] << 8) | src[i + 1];
        best.base = -1;
        cur.base = -1;
        for (i = 0; i < 8; i++) {
                if (words[i] == 0) {
                        if (cur.base == -1)
                                cur.base = i, cur.len = 1;
                        else
                                cur.len++;
                } else {
                        if (cur.base != -1) {
                                if (best.base == -1 || cur.len best.len)
                                        best = cur;
                                cur.base = -1;
                        }
                }
        }
        if (cur.base != -1) {
                if (best.base == -1 || cur.len best.len)
                        best = cur;
        }
        if (best.base != -1 && best.len < 2)
                best.base = -1;

        /*
         * Format the result.
         */
        tp = tmp;
        for (i = 0; i < 8; i++) {
                /* Are we inside the best run of 0x00's? */
                if (best.base != -1 && i >= best.base &&
                        i < (best.base + best.len)) {
                        if (i == best.base)
                                *tp++ = ':';
                        continue;
                }
                /* Are we following an initial run of 0x00s or any real hex? */
                if (i != 0)
                        *tp++ = ':';
                /* Is this address an encapsulated IPv4? */
                if (i == 6 && best.base == 0 &&
                        (best.len == 6 ||
                                (best.len == 5 && words[5] == 0xffff))) {
                        if (!inet_ntop4(src + 12, tp, sizeof tmp - (tp - tmp)))
                                return (NULL);
                        tp += strlen(tp);
                        break;
                }
                tp += SPRINTF((tp, "%x", words[i]));
        }
        /* Was it a trailing run of 0x00's? */
        if (best.base != -1 && (best.base + best.len) == 8)
                *tp++ = ':';
        *tp++ = '\0';

        /* Check for overflow, copy, and we're done. */
        if ((socklen_t)(tp - tmp) size) {
                //__set_errno (ENOSPC);
                return (NULL);
        }
        return strcpy(dst, tmp);
}
#endif /* INET_IPV6 */

/*!
 * \brief like inet_aton() but without all the hexadecimal and shorthand.
 *
 * \return 1 if `src' is a valid dotted quad, else 0.
 *
 * \note does not touch `dst' unless it's returning 1.
 */
static int inet_pton4(const char *src, u_char *dst)
{
        int saw_digit, octets, ch;
        u_char tmp[4], *tp;

        saw_digit = 0;
        octets = 0;
        *(tp = tmp) = 0;
        while ((ch = *src++) != '\0') {
                if (ch >= '0' && ch <= '9') {
                        u_int new = *tp * 10 + (ch - '0');
                        if (new > 255)
                                return (0);
                        *tp = new;
                        if (!saw_digit) {
                                if (++octets > 4)
                                        return (0);
                                saw_digit = 1;
                        }
                } else if (ch == '.' && saw_digit) {
                        if (octets == 4)
                                return (0);
                        *++tp = 0;
                        saw_digit = 0;
                } else
                        return (0);
        }
        if (octets < 4)
                return (0);
        memcpy(dst, tmp, 4);
        return 1;
}

#ifdef INET_IPV6
/*!
 * \brief convert presentation level address to network order binary form.
 *
 * \return 1 if `src' is a valid [RFC1884 2.2] address, else 0.
 *
 * \note
 *	\li (1) does not touch `dst' unless it's returning 1.
 *	\li (2) :: in a full address is silently ignored.
 */
static int inet_pton6(const char *src, u_char *dst)
{
        static const char xdigits[] = "0123456789abcdef";
        u_char tmp[16], *tp, *endp, *colonp;
        const char *curtok;
        int ch, saw_xdigit;
        u_int val;

        tp = memset(tmp, '\0', 16);
        endp = tp + 16;
        colonp = NULL;
        /* Leading :: requires some special handling. */
        if (*src == ':')
                if (*++src != ':')
                        return (0);
        curtok = src;
        saw_xdigit = 0;
        val = 0;
        while ((ch = tolower(*src++)) != '\0') {
                const char *pch;

                pch = strchr(xdigits, ch);
                if (pch != NULL) {
                        val <<= 4;
                        val |= (pch - xdigits);
                        if (val 0xffff)
                                return (0);
                        saw_xdigit = 1;
                        continue;
                }
                if (ch == ':') {
                        curtok = src;
                        if (!saw_xdigit) {
                                if (colonp)
                                        return (0);
                                colonp = tp;
                                continue;
                        } else if (*src == '\0') {
                                return (0);
                        }
                        if (tp + 2 endp)
                                return (0);
                        *tp++ = (u_char)(val > 8) & 0xff;
                        *tp++ = (u_char)val & 0xff;
                        saw_xdigit = 0;
                        val = 0;
                        continue;
                }
                if (ch == '.' && ((tp + 4) <= endp) &&
                        inet_pton4(curtok, tp) 0) {
                        tp += 4;
                        saw_xdigit = 0;
                        break; /* '\0' was seen by inet_pton4(). */
                }
                return (0);
        }
        if (saw_xdigit) {
                if (tp + 2 endp)
                        return (0);
                *tp++ = (u_char)(val > 8) & 0xff;
                *tp++ = (u_char)val & 0xff;
        }
        if (colonp != NULL) {
                /* Since some memmove()'s erroneously fail to handle
                 * overlapping regions, we'll do the shift by hand. */
                const int n = tp - colonp;
                int i;

                if (tp == endp)
                        return (0);
                for (i = 1; i <= n; i++) {
                        endp[-i] = colonp[n - i];
                        colonp[n - i] = 0;
                }
                tp = endp;
        }
        if (tp != endp)
                return (0);
        memcpy(dst, tmp, 16);
        return (1);
}
#endif /* INET_IPV6 */

const char *inet_ntop(int af, const void *src, char *dst, socklen_t size)
{
        switch (af) {
        case AF_INET:
                return inet_ntop4(src, dst, size);
#ifdef INET_IPV6
        case AF_INET6:
                return inet_ntop6(src, dst, size);
#endif
        default:
                /*__set_errno(EAFNOSUPPORT);*/
                return NULL;
        }
        /* NOTREACHED */
}

int inet_pton(int af, const char *src, void *dst)
{
        switch (af) {
        case AF_INET:
                return inet_pton4(src, dst);
#ifdef INET_IPV6
        case AF_INET6:
                return inet_pton6(src, dst);
#endif
        default:
                /*__set_errno(EAFNOSUPPORT);*/
                return -1;
        }
        /* NOTREACHED */
}

#endif /* NTDDI_VERSION < NTDDI_VISTA */

#endif /* _WIN32 */
